Housing and building exteriors are naturally subjected to environmental conditions that are destructive to the materials used to construct the exteriors. In particular, when natural materials are used, such as wood, rot and decay are the most common modes of exterior failure. Improperly situated siding materials cannot properly shield the interior surfaces to which they are attached, and are themselves subject to premature destruction, usually through invasion of moisture.
A common means for establishing housing and building exteriors is to use wood siding materials such as shingles in lap configuration. In view of the diminishing availability of certain siding materials, oriented strand board (OSB) siding has become pervasive in many parts of the world. Through the use of OSB materials, a structurally rated siding can be used, thereby eliminating conventional sheathing materials such as plywood sheathing. Moreover, conventional moisture barriers such as building paper are dispensed with since the OSB also acts as a moisture barrier.
It therefore becomes of paramount importance to establish a sound moisture barrier when using OSB siding. The predominant point of failure when using OSB occurs at the juncture between OSB panels. As shown in Prior Art FIG. 1, the abutting edges of two OSB panels 1 and 2 are separated by flashing 3. As is shown in more detail in Prior Art FIG. 2, this common flashing is characterized as having a first portion 4 and a second portion 6 connected by a transverse portion 5. The intended purpose of this flashing is to prevent water drip back from the bottom edge of panel 1 to the interior, and to provide a drip cap for panel 2. A common problem with this configuration, however, is that water tends to collect on the upper surface of transverse portion 5. Because in normal installations the upper surface is in direct contact with the lower edge of panel 1, rot and decay are in fact promoted as opposed to retarded.
A possible but labor intensive solution to this problem is to carefully space panel 1 from transverse portion 5. But given that each panel may weigh as much as 20 kilograms (50 pounds), such actions may be difficult if not impossible to achieve in an aesthetically pleasing manner.
Therefore, what is needed is a flashing that not only provides the desired water barrier between the environment and the interior surfaces to which the panels are attached, but also a means to prevent water accumulation at the lower edge of each panel. The present invention is intended to meet these needs.